textproduct: Albany

WHAT HAS CHANGED

The Storm Prediction Center has introduced a Marginal Risk (Level 1 of 5) for Severe Weather in portions of Ulster, Dutchess, and Litchfield County. The primary threat in any storm that reaches severe strength will be locally damaging wind gusts and moderate to heavy downpours.

KEY MESSAGES

1) Scattered to numerous showers and thunderstorms are expected again today, bringing the potential for locally heavy rain and isolated damaging wind gusts.

2) The combination of warm temperatures and very humid conditions will continue today, which will result in a risk for heat- related impacts, especially in eastern Ulster, western Dutchess and southern Litchfield CT.

DISCUSSION

KEY MESSAGE 1...

Falling heights aloft ahead of a deepening, upstream trough and warm, moist conditions within the northwest periphery of a Bermuda High will once again drive the chances for showers and thunderstorms across the region today. While there are still some questions as to the exact coverage due to inconsistent model guidance, the environment will be very similar to yesterday, suggesting the potential for scattered to numerous convective activity. And, given moderate to high instability (SBCAPE ~1000 to 2500 J/kg) along with high precipitable water content (PWATs ~1.5" to 2+"), the overall weak forcing should not be a significant inhibiting factor. That being said, this could pose a detriment to the development of severe-level convection. Poor mid-level lapse rates and very weak, deep-layer shear, in addition to this weak forcing, will make it difficult for storm organization and strengthening almost everywhere. The Storm Prediction Center has, however, introduced a Marginal Risk (Level 1 of 5) for Severe Weather across portions of Ulster, Dutchess, and Litchfield Counties where shear will be greatest. Here, an isolated severe storm or two will be possible with isolated damaging wind gusts the primary threat.

In fact, precipitation loading will likely contribute to gusty winds within any shower or storm today regardless of its strength. Likewise, any shower or storm will be capable of producing moderate to locally heavy downpours. The Weather Prediction Center has maintained its Marginal Risk (Level 1 of 4) for Excessive Rainfall across our area for today, suggesting the potential for isolated flash flooding. Given very wet antecedent conditions; slow storm motion; and the potential for training showers and storms, isolated flash flooding is a plausible hazard for today particularly for areas that had a heavier shower or storm yesterday.

Additional showers and possible thunderstorms linger into at least the first half of the weekend as the aforementioned trough and embedded shortwaves rotate through the region. PWATs won't be to the degree they are today given the Bermuda High looks to shift farther to the southeast, but locally moderate downpours will remain possible along with gusty winds. A Marginal Risk for Excessive Rainfall remains in place across our region for Saturday as well.

KEY MESSAGE 2...

The combination of high temperatures widely in the mid to upper 80s and dewpoints in the 60s to low 70s today will make for fairly unpleasant and uncomfortable conditions. However, the greatest feels-like temperatures, or heat index values will be found in portions of the lower Mid-Hudson Valley and southern Litchfield County. Here, heat index values in the upper 90s will increase the risk for heat-related illness particularly for those individuals who are susceptible to them. Therefore, a Heat Advisory remains in effect through 8 PM this evening. Drink plenty of fluids, limit time outdoors, and take frequent breaks in a cooled location in order to mitigate heat stroke and heat exhaustion.

AVIATION /12Z FRIDAY THROUGH TUESDAY/

Through 12z/Sat, low clouds/fog should gradually lift between 12Z-13Z/Fri, with VFR conditions then expected thereafter through this evening. However, isolated/scattered showers and thunderstorms will develop late this afternoon and may persist into Friday evening, producing brief periods of MVFR/IFR Vsbys. Patchy fog/low clouds may then redevelop in the wake of any showers/thunderstorms after 03Z/Sat producing some IFR/LIFR Vsbys/Cigs.

Light to calm winds will become west to southwest 5-10 KT by late this morning through this afternoon, then becoming light to calm once again after sunset. Winds will be stronger, and variable in direction in/near any thunderstorms.

Outlook...

Saturday Night: Moderate Operational Impact. Scattered SHRA. Sunday: Low Operational Impact. NO SIG WX. Sunday Night: No Operational Impact. NO SIG WX. Monday: Low Operational Impact. Slight Chance of SHRA...TSRA. Monday Night: Moderate Operational Impact. Chance of SHRA...TSRA. Tuesday: Moderate Operational Impact. Likely SHRA...TSRA.

ALY WATCHES/WARNINGS/ADVISORIES

CT...Heat Advisory until 8 PM EDT this evening for CTZ013. NY...Heat Advisory until 8 PM EDT this evening for NYZ064-065. MA...None. VT...None.